Fill in the blanks to make the correct statement.
The surface area of the cuboid formed by joining two cubes of side a face to face is ________.
we have, two cubes of side a.
These two cubes are joined face to face , then the resultant solid figure is a cuboid which has same breadth and height as the joined cubes has length twice of the length of a cube, i.e. l = 2a,b = a and h = a
Thus, the total surface area of cuboid = 2(lb + bh + hl)
= 2(2a × a + a × a + a × 2a)
= 2[2a2 + a2 + 2a2]
= 10a2